Reconsider double allocation/indirection on allocated storage

[arthurprs]

Even though double allocation/indirection allows for arguably simpler code and a lower-cost conversion from and into Strings (one allocation/deallocation is still required), it hurts creation and drop performance.

Clearly, this is a tradeoff, but I'd argue that string creation and drop are more prevalent than String/Vec conversion.

[polazarus]

My initial use case was String heavy but it's not the case anymore.
Another way will be to add yet another representation (like tokio's bytes)...

Thinking about it.

[polazarus]

On the way.